Ask HN: Is Modem Unlock is Illegal in your country?

How your ISP handle locked modem? In my country (Indonesia) ISP (Bolt) has jailed user in 2015 because he unlock modem for sell. I have some unused modem from Bolt and want to used with other ISP, but I wanna jailed, is this only happened in my country?

https://tekno.kompas.com/read/2015/05/06/11560047/Begini.Cara.Bolt.Melacak.Pelaku.Unlock.Modem